The most basic rice crispy treats only use rice crispy cereal (I used Trader Joe's new rice cereal!), marshmallows, and butter. Some people even omit the butter, but I wouldn't--especially when you brown it, it gives the treats a wonderful nutty flavor. Even the proportions are up to the cook: if you like yours more gooey, then more marshmallows, more crunchy, then more cereal, more taste, then more butter.
Yes. This is DEFINITELY my kind of "baking."
Lastly, the touch of salt that Deb adds in her recipe really heightens the flavor of the treat. However, if you aren't a fan of sweet savory combinations, omitting the salt is fine.